Humberstone is not anything you would imagine. The reason it was abandoned was something less sinister than a deadly extra terrestrial virus.
For awhile it was a prosperous town of 3500 that thrived on nitrate mining for fertilizer. These people had a town complete with a hospital, a public swimming pool, and even a theatre.
Then someday, someone came up with a way to make fertilizer through synthetic means: it’s cheaper to produce. Natural nitrate could not compete and the town slowly fell into decay. In 1960 Humberstone with its sister nitrate mining town, Santa Laura, were completely abandoned.